In general, the power of a pneumatic tool comes from a pressurized air that drives a pneumatic motor module of the pneumatic tool for the use of the pneumatic tool, wherein the pneumatic motor module controls and guides the flowing direction of the pressurized air to produce a clockwise or counterclockwise rotating state for the pneumatic tool. For example, an improved airflow control mechanism disclosed in R.O.C. Pat. Publication 569885 comprises: a cylinder having a cylindrical cylinder body; an air chamber disposed in the cylinder body, two directional air holes individually penetrating a corresponding wall at an end of a shaft of the cylinder body for connecting the air chamber with the external side of the cylinder body; an air valve having a circular body with its axial distal surface coupled to an axial distal surface of the cylinder body; two extending air holes separately extended in a predetermined direction from the cylinder body; two distal holes separately disposed at an axial distal surface of the cylinder body and on the internal circular surface of the cylinder body, and the two extending air holes are interconnected to the two directional air holes respectively; an adjusting member having a disc-shape base with a predetermined thickness and coaxially contained in the cylinder body and pivotally rotated in a clockwise position or a counterclockwise position, and the distal surfaces are connected to the internal circular surface; an air passage extended along the radial direction of the base; and an air outlet being an open end of the air passage disposed at a predetermined position of the distal surface of the base for interconnecting the air passage and a corresponding extending air hole.
From the description above, the pressurized air passes through the airflow passage of the adjusting member and enters into the clockwise air hole from the extending air hole of the air valve. It is worth to point out that the pressurized air has an air pressure greater than the atmospheric pressure, and thus the pressurized air is normally equalized with a position having a lower pressure in the environment. Airflow will be produced to form a fluid dynamical force, and the pneumatic tool uses such principle and the fluid dynamical force to drive the motor module. However, such patented technology has a problem that requires an air valve to be connected between the clockwise air hole and the air passage for adjusting and transmitting the pressurized air, and the high pressure of the pressurized air may leak from the gap between components gradually, so that the motor cannot maintain its expected horsepower, and thus lowering the efficiency of the pneumatic tool.
Effectively transmitting the pressurized air to the pneumatic tool and reducing the improper pressure leak to improve the efficiency of the pneumatic tool are the subjects for developers in the related field. This invention discloses a novel design of a pneumatic tool capable of minimizing the chance of an improper pressure leak of the pneumatic tool.